Manufacture of bleaching liquids.



HEINRICH WILSING, OF IBERNBURG, GERMANY.

MANUFACTURE ()IE" BLEACHING LIQUIDS.

No Drawing.

.To all whom it may concern:

Be it known that I, HEINRICH VVILsINc, chemist, a citizen of the German Empire, and resident of Bernburg, Dukedom of Anhalt, Germany, have invented certain new and useful Improvements in or Relating to the Manufacture of Bleaching- Liquids, of which the following is a specification.

My invention relates to a process for the manufacture of bleaching liquids by the actionof chlorin on alkaline-lyes and consists therein that the chlorin either in the form of gas or in liquid state is introduced into a liquid which contains at the same time alkaline-hydrate and alkaline-carbonate. This process results in the production of a bleaching liquid which contains as bleach-' ing agents free hypochlorous acid in addition to hypochloriteof alkali. The proportion of such bleaching agents may be varied according to requirements by suitably proportioning the contents of the alkaline-lyein alkaline-hydrate and in alkaline-carbonate. v v

Thereactions taking place may be seen from the following equations.

It appears that at first the'chlorin converts the whole of the sodium-hydrate and that then in accordance with the equation 2 the conversion of the carbonate takes place. Therefore in one single operation a bleaching lye is obtained which contains according to the proportion of carbonate to hydrate adopted a mixture of sodium-hypochlorite', free hypochlorous acid, sodium bicarbonate and sodium-chlorid. If as is advisable a small portion of the alkali is left uncombined, it will remain in the lye in the form of carbonate. V

The advantages of the invention are: great simplicity and easy control of the manufacture, high yield of active chlorin, high stability, and a proportion of free hypochlorous acid which can be regulated in accordance with the desired bleaching energy and the properties of the material to be bleached. Finally the presence of sodium-bicarbonate prevents the formation of Specification of Letters Patent. Application filed September 28, 1910. Serial N o.

l chlorin 60% Patented Apr. 16, 1912.

free hydrochloric acid from the hypochlorous acid during the bleaching process. Thestability of the bleaching liquid obtained in accordance with the invention appears from the fact that a liquid containing 17-32% of its active chlorin in form of free hypochlorous acid loses in 18 hours only l-j,3% of its active chlorin, whereas it has been found that electrolytic lyes which contain2%-5% of their active chlorin in the form of free acidlose in 18 hours 40-80% of their total bleaching chlorin (compare Kind and Weindel, Uompamtz'oe Investigations of OlzZom'n Bleaching lyes, Leipsic, 1909, page 20).

The process may be carried through as follows:v kg. of chlorin are caused to act in a slow jet, and avoiding strong heating,

on three cubic meters of a diluted alkaline lye containing 34.2 kg. of hydrate of soda and 41.6 kg. of carbonate of sodium, in a suitable apparatus provided with a stirring device. The chlorin is easily and completely absorbed, and 3.03 cubic meters of a bleaching liquid with 16.35 grams of bleaching chlorin per liter are obtained. Of the in round figures are in the form of sodium hypochlorite and 40% in the form of free hypochlorous acid. If desired, potassium carbonate and caustic potash can be used instead of sodium carbonate and caustic soda.

What I claim is:

1. A process for bleaching liquids by the manufacture of the action of chlorin on alkaline lyes consisting in introducing chlorin into a liquid containing alkaline hydrate with alkaline carbonate.

In a process for the manufacture of bleaching liquids by the action of chlorin on alkaline lyes containing alkaline hydrate with alka ine carbonate proportioning the alkaline hydrate to alkaline carbonate so as to produce free hypochlorous acid 1n ad dition to hypochlorite of alkali in a proportion according to requirements.

In testimony whereof,--I aflix my slgnature in presence of two witnesses.

HEINRICH WILSING. Witnesses HENRY HAsPER, WOLDEMAR HAUPT. 

